Rail-bond.



No! 834,689 PATENTED OCT. 30, 1906.

' G. R. STURDEVANT.

' RAIL BOND.

APPLICATION FILED JULY 7, 19.05.

WED T T S 12mm OFFICE";

CHARLES R. STURDEV'ANT, 0F. WORCESTER, MASSACHUSETTS; ASSIGNOR i T0AMERICAN STEEL .& WIRE COMPANY, or WORCESTER, MAssAouu- SETTS, AOORPORAT1 ON OF NEW JERSEY. I RAlL-BOND.

To all whom it concern. i

Be it knownthat I, CHARLES R. STUR E- 'VANT, a citizen of the UnitedStates, residing at Worcester, county of'Worcester, State of the same.

My invention relates to certain new and useful improvements inra'ibbonds for elec-.

. trical railways or connections for electrical conductors, and has forits objects to provide a bond with an improved form of terminal whichcan be effectively driven into a bottomed cavity or cup-shaped hole inthe rail;

to {provide a rail-bond having terminals which may be so applied to theconductorvrailas toinsure permanent and efficient con tact and whichwill obviate the disadvantages inherent in most of the devices hereto- 1fore employed and the modes of applying the F 5 same; to provide a jointbetween the-terminal and the rail having a greater contact area than-hasbeen possib1etoobtain heretofore, and'a consequent decrease incontact'resistance; to lower the cost of installation and viating' thenecessity of using compressors,

facilitate the application of the bond by oband to'greatly reduce theliability of corro sion of the contact-surfaces between thebondterminals and the rail. Other objects of the tion showing thecompleted joint; Fig. 4 is invention will appear more fully hereinafter.

v In the accompanying drawings, Figure 1 is a transverse section throughone terminal of the bond and the cooperating conductorrail, showing theterminal in the initial stage 'of its application. -Fig. 2 is acorresponding .view showin the-terminal in the succeeding stage of appication. Fig. 3 is a similar seca-view similar to Fig. 3, illustratingaslightlymodified construction of terminal and cup;

shaped cavity in the conductor-rail.-

'Incarryi'ng out my invention I fprovide a connector for theadjacentends o the conductor-rails comprising the usual flexiblecondu'ctor', which may take the form of a bundle of twisted wirestrands, intimately connect 1 ed-with the terminals which en age therailsections. Each ofsaid ,termina sconsists of Patented Oct. 30,1906.

is attached, anda stud portion 0, projecting, from the inner facethereof, which stud has the body portion 6, to which the connectora adiameter preferably greater than its len th,

and a boss or projection don the outer ace of the terminal, which bossor. projection lies within or is included within the lateral walls ofthe .terminal and is preferably of less 'The length of the terminalstudc which enters the cavity or cup-shaped o'peningfin cross-sectionalarea than the stud'portion c.

y part way through the: i the rail, leaving a fin' or web 9,

the conductor-rail is preferably-made from one-half tothree-fourths ofthe diameter ,of..

said'stud portion and a little greater than the depth, of thehole f forbest results. The

metal which constitutes the boss cl'on 'the outer face of theterminal,together with that which forms the stud .portion 0, is sufficient toentirely fill the opening in the rail and to. overflow the ed es of thehole upon the surface of the rai and form a projection or shoulder 1cunder the action of heavy hammer-blows, thus increasin the contact-sun.

face between the terminal and the rail and effectively sealing thejoint. The terminals may of course be1-made of any appropriatemetahthough it is customary and preferable to use copper for thispurpose, owing to its hi h conductivity and plastic roperties' napplying a bond of the c aracter hereinbefore escribed 'a' hole f isdrilled to anfy desired depth in the rail-section e, and 'pre erably,though not necessarilyia bright metallicannular surface is pro uced onthe rail adjacent to' the opening, The bottom of the cup-shaped hole oropening may be made uite flat in thin rail-sections, as shown in igs. 1,2', 3, and 4, or said bottom portion may be given a conical form withoutseri-.

-'Ioo ously affecting the efficiency of the joint, it

being evident that the exact contour of the opening in the rail or theform of the bottom thereof is not essential. Thestnd portion .0, of theterminal is inserted in the/ cupshaped hole f and subjected totheapplica tion of a few heavy blows by a sledge-hamthe rail about theedgeof the hole at one or more places, so as to upset the metal around theedge of the hole and force the small portions it thereof into thebody'of the stud 0,-

which serves to hold the terminal rigidly in position in the cup-shapedopening in the rail. It has been found that three such indentations orprojections render it quite impossible toremove or loosen the terminal;

- but of course any desired number of such indentations may be made.After these .indentations havebeen made the terminal is furthersubjected to the riveting action of the hammer until the terminal takesthe general'ly-finished form as shown in Fi 3.

' During this operation the metal wi l be forced into the cavity orcup-shaped opening and will completely fill overy pore and minutedepression of the wall about the hole in the rail; This construction ofterminal and cup-shaped opening and the mode of applying the terminal tothe opening makes an'extremely rigid and permanent joint of very hihconductivity which absolutely excludes t e air and moisture which wouldtend to corrode the same. The operation of hammering the copper into thehole rapidly hardens it and renders the joint all the more secure andpermanent. prick-punch depressions in the lateral Walls of the hole f,as shown at Z'in Fig. 4, or by drilling, threading, or otherwiseslightly indenting or roughening the Wall of the cavity, the copper ofthe terminal will be forced into the depressions thus formed, and as thecross-sectional area of the cavity through these depressions will beincreased over that at the entrance of said cavity the connectionbetween the rail and the terminal will be, in

' effect, a dovetailed joint and the terminal will be renderedcorrespondingly more ri id, though, of course, it is to be understood tat the application of this roughening or indenting of the surface is notessential to the sucthese respects.

By making small cess of the invention.- the bond connecting theterminals may .be of any desired capacitg or of any preferred form orconstruction an arrangement of strands or laminations. It is alsoobvious that the terminals maybe connected to the body portion I) in anysuitable manner that may be desired, and it is to be understood that theinvention ifs not to be limited or restricted in Having ,thus describedmy invention, what 1. A rail-bond-, comprising a connectingbody and,solid metal terminals, each of said terminals having an integral boss orenlargement 'o'nits outer face of less cross-sectional area than theremainder of the terminal.

2. A rail-bond, comprising a connectingbody and solid metal terminals,each of said terminals having an integral boss or enlargement on itsouter face, and a stud on its inner face, the diameter of the studsbeing greater than their length, and the cross-sectional area of thebosses or enlargements being less than that of the studs.

' 3. A rail-bond, provided with-a metal terminal having a stud on oneface and a boss or projection on the opposite'face thereof, said bosslying within the cross-sectional area of the stud, and a conductor-railhaving a bottomed cavity to receive the terminal stud. 4. A rail-bond,provided with a solid metal terminal stud, and a conductor-rail havingbottomed-cavity to receive said'terminal stud, the cross-sectional areaof said cavity being increased below the entrance or initial portion ofsaid cavity. i

5. A rail-bond, provided with solid metal terminals, each having a studonone face and a reduced boss on the other face thereof, andconductor-rails havin hollow cupshaped openings to receive the studs ofsaid terminals, the crosssectional area of each cavity being. increasedbelow the entrance or initial portion thereof.

' In testimony whereof I ailix my signature in presence of twowitnesses.

CHARLES R. STURDEVANT. Witnesses H. M. LA'IHAM, THos. MAODUFF.

The body portion' of

